Thinks: A Novel Tool For Multiscale Cfd Calculations Of The Cerebral Vasculature

Background: Computational Fluid Dynamics (CFD) is emerging as a tool for better assessment and management of cerebral aneurysms. However, CFD calculations are often restricted to a small arterial zone and the solution could be inaccurate depending on the boundary conditions prescribed. A 1D simulation of the complete vessel network, THINkS (Total Human Intravascular NetworK Simulation), is introduced to better describe boundary conditions and to provide flow information related to the complete complex vessel network. Methods: THINkS is a modifiable, 1D network simulation of the complete human blood circulatory system. A validation of THINkS was performed using volumetric flow rates recorded in the cerebral vasculature waveforms over the cardiac cycle. Validated waveforms of the; (1) ICA proximal to the siphon, (2) ICA proximal to circle of Willis (CoW), and (3) mid- basilar artery were obtained. THINkS predictions were compared to the experimental bounds for both absolute and dimensionless flow rate quantities. Results: THINkS calculations indicated usefulness of the model in predicting the trends of cerebral flow patterns. THINkS solutions were validated with a number of in vivo experimental data and the agreement was excellent. A comparison with experiments for the impact of incomplete CoW to the flow patterns was also made and the trend shows an excellent agreement with reported data. Conclusion: THINkS allows for more accurate boundary conditions for 3D zonal-based CFD calculations. THINkS has been validated against available experimental data and shown to respond correctly to the flow pattern change caused by the variation in CoW. It provides the detailed flow information of the entire human body including cerebral vessel network. Our aim is to use THINkS to generate accurate flow assessments, guide surgical treatment plans, and more reliably predict risks associated with vascular lesions.